@article{MunchelHoangZhaoetal.2015, author = {Munchel, Sarah and Hoang, Yen and Zhao, Yue and Cottrell, Joseph and Klotzle, Brandy and Godwin, Andrew K. and Koestler, Devin and Beyerlein, Peter and Fan, Jian-Bing and Bibikova, Marina and Chien, Jeremy}, title = {Targeted or whole genome sequencing of formalin fixed tissue samples: potential applications in cancer genomics}, series = {Oncotarget}, volume = {6}, journal = {Oncotarget}, number = {28}, issn = {1949-2553}, doi = {10.18632/oncotarget.4671}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-6307}, pages = {25943 -- 25961}, year = {2015}, abstract = {Current genomic studies are limited by the poor availability of fresh-frozen tissue samples. Although formalin-fixed diagnostic samples are in abundance, they are seldom used in current genomic studies because of the concern of formalin-fixation artifacts. Better characterization of these artifacts will allow the use of archived clinical specimens in translational and clinical research studies. To provide a systematic analysis of formalin-fixation artifacts on Illumina sequencing, we generated 26 DNA sequencing data sets from 13 pairs of matched formalin-fixed paraffin-embedded (FFPE) and fresh-frozen (FF) tissue samples. The results indicate high rate of concordant calls between matched FF/FFPE pairs at reference and variant positions in three commonly used sequencing approaches (whole genome, whole exome, and targeted exon sequencing). Global mismatch rates and C·G > T·A substitutions were comparable between matched FF/FFPE samples, and discordant rates were low (<0.26\%) in all samples. Finally, low-pass whole genome sequencing produces similar pattern of copy number alterations between FF/FFPE pairs. The results from our studies suggest the potential use of diagnostic FFPE samples for cancer genomic studies to characterize and catalog variations in cancer genomes.}, language = {en} }